Redundant wan setup

[Thomas Six]

Our customer wants to make the WAN connection to the 3CX server redundant. This ensures that when the primary internet provider goes down, the secondary connection takes over. Therefore, the FQDN customer.3cx.be should point to two WAN IP addresses. Is this possible? And if possible how to configure?

 

[Alphabetic]

You could always set your network to dynamic then when the WAN fails over, the IP will update.

 

[KyriacosS_3CX]

Hello,

Can you elaborate a little? Where is the PBX deployed? Who/how is connecting to it? How is the WAN redundancy set-up?

On-Prem? Then the WAN of their office doesn't matter for internal connections, they should be using local DNS to reach the internal IP (or have their border router doing hairpin NAT). It might matter for SIP Trunks and mobile users

On some cloud provider? Then again the WAN connection of their office should not matter at all, that would not impact the PBX beyond needing to whitelist both IPs on it.

We are missing some info here I think.

 

[SteveITS]

@ Thomas Six
If they have the need and budget, perhaps SD-WAN.

 

[Kevin Attard Compagno]

As @KyriacosS_3CX pointed out, we need a better understanding of your setup. The key question is: where is the PBX? In-cloud or on-prem?

 

[Thomas Six]

Hello, thanks for the reply. It's an on prem installation with remote offices. They are using a 3cx.be fdqn. When I set wan ip to dynamic and there is a wan failover, after 5 minutes everything is up and running again via the backup internet line.
We will manually switch to the primary line again, when this comes online.

 

[KyriacosS_3CX]

Is the PBX the only service being accessed remotely? How are other services handled?

I think having a VPN between the two sites with local DNS pointing the pbx FQDN to the local, through the VPN, IP is one solution. the VPN endpoint can sit behind the two WAN endpoints, making it agnostic of the actual IPs - it will need to be re-established whenever the IP changes, but if the HQ is the initiator this can be automatic.